Thermoforming packaging machine, method and packaging

ABSTRACT

The invention relates to a method, a thermoforming packaging machine and a packaging with a hinged lid that is produced according to the method or by means of the thermoforming packaging machine.

CROSS-REFERENCE TO RELATED APPLICATIONS

This Application claims priority to German Patent Application Number 102015205221.4 filed Mar. 23, 2015, to Rudolf von Sybel, currently pending, the entire disclosure of which is incorporated herein by reference.

FIELD OF THE INVENTION

The invention relates to a method, to a thermoforming packaging machine and to a packaging.

BACKGROUND OF THE INVENTION

Packagings that are manufactured by means of a tray and a film web on a tray sealing machine are known from WO 2012/087114 and U.S. Pat. No. 4,079,567. In each of these documents, the goal is to produce a packaging with a resealable lid without sealing a prefabricated lid onto the tray.

SUMMARY OF THE INVENTION

One object of the present invention is to be able to produce a packaging with a resealable lid on a thermoforming packaging machine and therefore on another machine type.

The method according to one embodiment of the present invention for the operation of a thermoforming packaging machine comprises the following steps:

forming of a trough and creating a flange surface that surrounds the trough in a generally peripheral way into a first film web in a forming station,

creating a cutting line into the first film web within the flange surface in a cutting station that is disposed in a processing direction downstream of the forming station,

creating an internal sealed seam between the flange area and a second film web in a first sealing station that is disposed downstream of the cutting station in order to place the second film web on the flange area in a gas-tight way, whereby the internal sealed seam is created between the cutting line and the trough in a top view of the trough, and

creating an external sealed seam between the second film web and the flange area, whereby the external sealed seam is created outside of the cutting line in a top view of the trough.

This method can allow for the production of a packaging with a hinged lid using only a first and a second film web (i.e. a bottom film and a top film) without the need to put on an additional lid after inserting the product in the trough and prior to sealing.

The cutting line may be formed with at least one substantially U-shaped course in order to allow for a hinge function on a fourth side.

In one embodiment, the internal and the external sealed seam are created together in the first sealing station. Hence, only a single sealing station is provided for, and the packaging machine does not have to be prolonged unnecessarily and/or the mounting surface is minimized.

In another embodiment, the external sealed seam is created in a second sealing station that is disposed downstream after the first sealing station. This embodiment allows for two sealing stations designed in a structurally simple way, whereby the sealing pressures and sealing temperatures in the two stations can be adjusted differently in a known way.

For practical reasons, the external sealing seam can be mostly formed congruently to the cutting line, in particular also in a U-shaped way, to achieve a visually appealing packaging.

The external sealed seam may be a non-detachable connection and the internal sealed seam may be a detachable connection between the first and second film web in order to simplify handling during opening of the packaging by the consumer.

A thermoforming packaging machine according to one embodiment of the present invention that can be operated in particular according to the method described before can comprise a forming station for thermoforming of a trough into a first film web, a first sealing station and a cutting station that is disposed between the forming station and the sealing station. The cutting station has a cutting tool in order to insert a cutting line within a flange surface that surrounds the trough in a generally peripheral way, whereby the first sealing station has an internal sealing tool that is configured to create an internal sealed seam between the cutting line and the trough in the flange surface. Furthermore, an external sealing tool may be provided in order to create an external sealed seam outside of the cutting line in the flange surface. Through cutting into the first film web even ahead of a sealing station, the area of the lid that is to be removed from the trough during opening of the packaging can be determined, and the lid can be created through the subsequent external sealed seam whereby it is placed non-detachably on the trough by means of a hinge seal.

The cutting tool can have a cutting edge with a U-shaped course that is particularly suitable, especially in case of rectangular but also round or oval packagings, to be drawn near to the external contour of the packaging.

Both sealing tools can be provided in the first sealing station.

In another embodiment, the external sealing tool is provided in a second sealing station that is disposed downstream of the first sealing station.

The external sealing tool may be formed in a mostly congruent position to the course of the cutting edge of the cutting tool in order to allow for a shapely packaging.

A packaging according to one embodiment may be manufactured in accordance with one of the methods described before or on a thermoforming packaging machine described before.

The flange surface thereby can have a U-shaped cutting line in the first film web and the flange area can have a surrounding, closed and gas-tight internal sealed seam within the cutting line and outside of the trough. In addition, the flange surface may have an external sealed seam outside of this cutting line.

The external sealed seam may be a non-detachable connection and the internal sealed seam may be a detachable connection between the first and second film web.

The packaging can have a straight and non-detachable sealed seam on one side on which its flange surface does not have a cutting line in order to form a hinge for a hinged lid, whereby the hinged lid may be formed of an external part of the flange surface and the second film web.

Other and further objects of the invention, together with the features of novelty appurtenant thereto, will appear in the course of the following description.

DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

A preferred embodiment of the invention will be explained in greater detail by means of a drawing in the following. The figures show:

FIG. 1 is a schematic side view of a thermoforming packaging machine according to one embodiment of the present invention;

FIG. 2 is a schematic top view of a film web according to one embodiment of the present invention;

FIG. 3 is a top view of a packaging according to one embodiment of the present invention;

FIG. 4 is a side view of a closed packaging according to one embodiment of the present invention; and

FIG. 5 is a side view of an opened packaging according to one embodiment of the present invention.

Identical components are marked continuously with identical reference signs in the Figures.

DETAILED DESCRIPTION OF THE INVENTION

The invention will now be described with reference to the drawing figures, in which like reference numerals refer to like parts throughout. For purposes of clarity in illustrating the characteristics of the present invention, proportional relationships of the elements have not necessarily been maintained in the drawing figures.

The following detailed description of the invention references specific embodiments in which the invention can be practiced. The embodiments are intended to describe aspects of the invention in sufficient detail to enable those skilled in the art to practice the invention. Other embodiments can be utilized and changes can be made without departing from the scope of the present invention. The present invention is defined by the appended claims and the description is, therefore, not to be taken in a limiting sense and shall not limit the scope of equivalents to which such claims are entitled.

FIG. 1 shows a schematic side view of a thermoforming packaging machine 1 according to one embodiment of the invention with a forming station 2, a cutting station 3 with a cutting tool 16 that has a cutting edge 16, a filling station 4, a first evacuating and sealing station 5 with an internal sealing tool 30 and transversal and longitudinal cutting devices 6, 7 that are disposed in this order in a processing direction R on a machine frame 8. At the input side there is a feed roller 9 on the machine frame 8 from which a first film web 8, which is also called lower film, is unrolled. In the processing direction R following the first sealing station 5, a second sealing station 13 with an external sealing tool 40 may be provided in order to place a further sealed seam or to modify and/or to seal an existing sealed seam more firmly.

On the output side, a discharge device in the form of a conveyor belt 14 can be provided on the thermoforming packaging machine 1 that is used to transport finished occasional packs 15 away. Further, the thermoforming packaging machine 1 may have a feeding device that grips the lower film 10 laterally and transports it further in the processing direction R by cycles (intermittently) in a main operating cycle. The feeding device can, for example, be implemented through laterally disposed transport chains, lateral grippers or friction rollers.

In the illustrated embodiment, troughs 17 are formed of the lower film 10 in the forming station 2 by means of thermoforming. The forming station 2 can thereby be formed in a way that several troughs 17 are formed next to each other in the direction that is perpendicular to the processing direction R.

The evacuating and sealing station 5 may be formed as a closed chamber in which the atmosphere in the packs is evacuated prior to sealing and, where required, substituted by a replacement gas such as CO2 as a protective gas.

FIG. 2 shows a schematic top view of the thermoforming packaging machine 1 in the processing direction R in an area from the forming station 2 up to the second sealing station 13. The lower film 10 extends in its width between two continuous lines at the top and at the bottom of the drawing. In the illustrated embodiment, a so-called format with a row RE and three lanes SP is shown; consequently a format with three packs can be processed in each station. In the forming station 2, three troughs 17 are thermoformed and/or shaped into the lower film 10. The dotted line L that surrounds the trough 17 defines a flange surface F outside of the trough edge 17 a of each trough 17. A distance A can be provided between two laterally adjacent flange surfaces F on which the longitudinal cutting device 7 shown in FIG. 1 cuts out a central strip in the width of the distance A and thereby separates the packs 15.

In the cutting station 3, a cutting line 18 that is generally U-shaped in a top view can be produced into the lower film 10 within the flange surface F by means of a cutting tool 16 that is not illustrated in greater detail here. In this context, the term “cutting line” 18 can mean that the lower film 10 is severed and/or cut or punched along this cutting line 18. In the filling station 4 that is situated downstream of the cutting station 3, one or several products 19 are inserted in the troughs 17.

In the first sealing station 5, the upper film 12 can be supplied from a feed roller 11 and an internal sealed seam 20 can be produced between the lower and the upper film 10, 12 by means of an internal sealing tool 30 that is not illustrated in greater detail here after the inside of the trough 17 is evacuated and/or gassed. The internal sealed seam 20 may be situated within the cutting line 18 and along or outside of the trough edge 17 a as a closed and gas-tight sealed seam whereby this sealed seam may be formed as a detachable sealed seam, i.e., a so-called peel seal that can be detached easily during opening of the packaging 15 by the consumer.

In the second sealing station 13, the upper film 12 can be sealed onto the lower film with a further sealed seam (i.e., the external sealed seam 21) outside of the cutting line 18 and within the flange surface F along or in congruence with the cutting line 18. The external sealed seam 21 may be designed by means of an external sealing tool 40 that is not illustrated in greater detail as a non-detachable sealed seam, a so-called hard or firm seal so that a lid is created that is formed of the upper film 12 and the U-shaped part of the flange surface F along but outside of the cutting line 18. In the second sealing station 13, a further sealed seam 22, which can be designed as a straight line and spatially separated from the external sealed seam 21 and also in a non-detachable way, may be created in order to faun a hinge. The hinge can be provided on the side on which there is no cutting line 18, i.e., on the open side of the U-shaped course of the cutting line 18. The invention also covers an embodiment in which the internal 30 and external sealing tool 40 are provided both in the first, and in this case only, sealing station 5. Furthermore, the invention covers an embodiment in which the first sealing station 5 creates an internal sealed seam 20 and an external sealed seam 21, whereby both sealed seams 20, 21 are at first designed as detachable seals and whereby the external sealed seam 21 is re-sealed in the second sealing station 13 in order to obtain a non-detachable external sealed seam 21.

FIG. 3 shows a top view of a packaging 15 according to one embodiment of the invention in an enlarged view with its trough 17 in which the product 19 is located. Between the trough edge 17 a and the cutting line 18, the internal sealed seam 20 is shown as a surrounding and closed sealed seam. The external sealed seam 21 may be positioned outside of and along the cutting line 18 and still within the flange surface F. The external sealed seam 21 can be designed as a continuous but open sealed seam. Likewise, it is possible that the external sealed seam 21 is designed of a plurality of seal sections, to seal the upper film 12 onto the area of the flange surface F outside of the cutting line 18 in order to form the lid.

FIG. 4 shows a lateral section view of the closed packaging 15. On the left side of the trough 17, the cutting line 18 is shown in the area of the flange surface F. To the right of the cutting line 1B, the internal sealed seam 20 is shown and to the left of the cutting line 1B, the external sealed seam 21 is shown. On the right side of the trough 17, the internal sealed seam 20 and the further sealed seam 22 that can form a hinge are shown in the area of the flange surface F.

FIG. 5 shows a lateral section view of the opened packaging 15. The upper film 12 together with the part of the flange surface F that forms a hinged lid 50 through the external sealed seam 21 of the upper film 12 is illustrated as lifted upwards on the left side. The upper film 12 may be detached in the process along the detachable internal sealed seam 20 in order to create an aperture to remove the product 19 wholly or in part and to also put a part back into the trough 17, where required, to subsequently place the hinged lid 50 and/or the upper film 12 back onto the flanged surface F along the previous internal sealed seam 20.

From the foregoing, it will be seen that this invention is one well adapted to attain all the ends and objects hereinabove set forth together with other advantages which are obvious and which are inherent to the structure. It will be understood that certain features and sub combinations are of utility and may be employed without reference to other features and sub combinations. This is contemplated by and is within the scope of the claims. Since many possible embodiments of the invention may be made without departing from the scope thereof, it is also to be understood that all matters herein set forth or shown in the accompanying drawings are to be interpreted as illustrative and not limiting.

The constructions and methods described above and illustrated in the drawings are presented by way of example only and are not intended to limit the concepts and principles of the present invention. Thus, there has been shown and described several embodiments of a novel invention. As is evident from the foregoing description, certain aspects of the present invention are not limited by the particular details of the examples illustrated herein, and it is therefore contemplated that other modifications and applications, or equivalents thereof, will occur to those skilled in the art. The terms “having” and “including” and similar terms as used in the foregoing specification are used in the sense of “optional” or “may include” and not as “required”. Many changes, modifications, variations and other uses and applications of the present construction will, however, become apparent to those skilled in the art after considering the specification and the accompanying drawings. All such changes, modifications, variations and other uses and applications which do not depart from the spirit and scope of the invention are deemed to be covered by the invention which is limited only by the claims which follow. 

What is claimed is:
 1. Method for operating a thermoforming packaging machine, said method comprising the steps of: forming a trough into a first film web in a forming station; creating a flange surface that at least partially surrounds the trough; creating a cutting line into the first film web within the flange surface in a cutting station that is disposed in a processing direction downstream of the forming station; creating an internal sealed seam between the flange surface and a second film web in a first sealing station that is disposed downstream of the cutting station in order to place the second film web onto the flange surface, wherein the internal sealed seam is created between the trough and the cutting line; and creating an external sealed seam between the second film web and the flange surface, wherein the external sealed seam is created outside of the cutting line.
 2. Method according to claim 1, wherein the cutting line is U-shaped
 3. Method according to claim 1, wherein the internal sealed seam and the external sealed seam are created together in the first sealing station.
 4. Method according to claim 1, wherein the external sealed seam is created in a second sealing station that is disposed downstream from the first sealing station.
 5. Method according to claim 1, wherein the external sealed seam is U-shaped.
 6. Method according to claim 1, wherein the external sealed seam is a non-detachable connection and the internal sealed seam is a detachable connection between the first film web and second film web.
 7. Thermoforming packaging machine comprising: a forming station for thermoforming a trough into a first film web; a first sealing station including an internal sealing tool that is configured to create an internal sealed seam between the cutting line and the trough in the flange surface; a cutting station disposed between the forming station and the first sealing station, wherein the cutting station includes a cutting tool to create a cutting line within a flange surface that surrounds the trough; and an external sealing tool that is configured to create an external sealed seam outside of the cutting line in the flange surface.
 8. Thermoforming packaging machine according to claim 7, wherein the cutting tool has a cutting edge with a U-shaped course.
 9. Thermoforming packaging machine according to claim 7, wherein both the internal sealing tool and the external sealing tool are provided in the first sealing station.
 10. Thermoforming packaging machine according to claim 7, wherein the external sealing tool is provided in a second sealing station that is disposed downstream of the first sealing station.
 11. Packaging manufactured according to the method of claim
 1. 12. Packaging comprising: a trough formed in a first film web; a flange surface that at least partially surrounds the trough; a U-shaped cutting line for fled into the flange surface; a closed and gas-tight internal sealed seam created between the trough and cutting line; and an external sealed seam created outside of the cutting line.
 13. Packaging according to claim 12, wherein the external sealed seam is a non-detachable connection and the internal sealed seam is a detachable connection between the first film web and second film web.
 14. Packaging according to claim 12 further comprising a straight, non-detachable sealed seam created on a side of the flange surface having no cutting line in order to form a hinge for the hinged lid, wherein the hinged lid is formed of a part of the flange surface that is located outside of the cutting line and the second film web. 